Comparative Study of Various Organic Fertilizers Effect on Growth and Yield of Two Economically Important Crops, Potato and Pea

In the present experiment, the effect of various house hold wastes i.e. T1 (egg shell powder), T2 (wood ash), T3 (banana peel), T4 (used tea waste), T5 (egg shell tea) and T6 (control) used as organic fertilizers on growth and yield of two important vegetables i.e. potato and pea was investigated. Among all the treatments, the minimum average number of days to germination was observed in T3 in both potato and pea. The overall growth and development of potato and pea plants increased and the average plant height after 30, 60 and 90 days was greater in plants of treatment T1 (egg shell powder). In case of potato, the highest mean plant height (14.75 cm) was observed in treatment T1, followed by T3 and T4 (10.62 cm and 9.87 cm) respectively after 90 days of the emergence. T1 treatment increases the no. of leaves, no. of nodes, no. of branches and leaf area. Regarding tuber yield, the tubers were classified as large (>30 grams), medium (15 30 grams) and small (0.4 15 grams). T1 treatment produced greater average number of large size tubers (2.25) per plant, followed by T3 (1.25); however, the medium and small tubers followed comparable trends with differences among treatments. The average tuber yield (per potato plant) in treatment T1 was higher (113.78 g). In case of pea, T4 treatment (used tea waste) showed the highest mean plant height (82.25 cm). The treatment T1 (eggshell powder), T3 (banana peel) and T4 (used tea waste) showed positive effect on average pod yield (64.82 g, 66.67 g and 114.35 g) respectively. Number of grains per pod and pod size has been found higher in case of treatment T4. It has been concluded that among the different organic treatments, eggshell powder, banana peel and used tea waste were found best as organic fertilizer source for the two vegetables i.e. potato and pea.


Introduction
Agriculture was practiced for thousands of years without using any artificial chemicals. Soil management practices have recently increased the use of chemical fertilizers to help crop yields by improving nutrient supply. Use of these agrochemicals not only causes the degradation of cultivable land but also increases agricultural pollution. In order to overcome this situation, organic farming is the only solution in which only natural resources such as organic matter, plant and animal wastes and microbes are implied [1]. Use of organic manures has improved soil fertility and helps in combating pest and disease problems [2] [3] [4].
The use of homemade organic fertilizers is considered an environment friendly means to reduce the waste growing into landfill. Pakistani soil is deficient in organic matter than the recommendable level. 1.29% carbon in soil is considered to be enough in organic matter, but most of the Pakistani soils have less than 1% [5].
Approximately 35 kinds of different vegetables are cultivated in numerous agro-ecological areas of Pakistan. Potato occupies the largest area (34.01%) among vegetable production [6]. In Pakistan, the pea is also an important crop occupying 3rd position among the major leguminous crops [7] [8]. In Pakistan, the yield of potatoes and peas per hectare is very low as compared to advanced countries. Imbalance use of fertilizers is one of the major factor due to which production is declining continuously every year [9].
The major factor responsible for the rapid plant growth is the nutritional access in the soil. Deficiency of one nutrient in the soil may influence greatly the levels of other nutrients and their availability [10] [11].
The awareness of environment and food safety issues is responsible for the development of organic farming in the recent years [12] [13]. Eggshells wastes can be used as a plant fertilizer because eggshell contains 95% calcium carbonate and is potent source of lime [14] to neutralize the pH of acidic soil. A study demonstrated that plants of red clover when grown on eggshells fertilized soil grew 10 mm larger than the plants without eggshells [15]. Boiled Tea Waste (formed after making tea) is also used for correcting the pH of soil and is a good source of Tannic Acid which helps to neutralize the soil. Tea leaves contain potassium (K), phosphorous (P) and Nitrogen (N), which are important elements for plant growth. When tea mixed with the soil, it improves the nutrient retention of the soil which can stimulate the plant growth.
Banana peels contain the three macronutrients i.e. Nitrogen, Phosphorus and Potassium, as well as many micronutrients, which promote the growth of garden plants from seed germination to blooms and fruits. Because of these nutrients, banana peels also help plants to resist against diseases [16]. Ash can be used for growing garden plants. The main constituents of ash are calcium, iron, magnesium, aluminum, potassium, sodium, silicone and titanium [17]. Insam  Organic manuring is becoming an important part of environmentally sound sustainable agriculture. Residual nature of organic sources makes them more value based for the whole system as compared to individual crops [19]. Recently, farmers' choice is diverted to organic farming instead of chemical fertilizers because of their high cost and inefficiency to improve soil fertility [20]. Therefore, the purpose of present research was to evaluate the effect of different types of house hold waste as organic fertilizers on potato and pea plant growth and yield and an alternative utilization of house hold waste in an economically environment friendly manner.

Material and Methods
The present research work was conducted in the Green house at Hazara Agri-

Experimental treatments
Eggshell Powder (T1) The eggshells were collected from household kitchen and bakery and dried in the shade, then grinded using household grinder. 3 tablespoons full (45 g) of eggshell powder per pot was added and mix well with the pot soil. Single seed of each vegetable i.e. potato and pea was planted per pot ( Figure 1).

Wood ash (T2)
Wood ash is the remainder after combustion of wood and wood products (chips, Sawdust, bark etc.).Wood chips and sawdust was collected from furniture market and burned to make the ash. The wood ash was mixed with the pot soil @ 3 tablespoons full (11.7 g) per pot ( Figure 1).

Banana peels (T3)
Banana peels were collected from house hold kitchen and fresh fruit juice  The used tea waste was collected from household kitchens and local tea shops and dried in the shade then mixed with pot soil @ 3 tablespoons full (15.9 g) per pot.
Eggshell Tea (T5) The eggshell tea was made by boiling 3 tablespoon full (45 g) of crushed eggshell powder per liter of water for about one minute. The tea was allowed to cool and let it for 24 hours to release nutrients into the water more efficiently and then the supernatant was filtered in the bottle. The eggshell tea was used at the rate of 1000 ml tea per pot.

Control (T6)
In the control treatment no organic fertilizer was mixed with the pot soil.

Soil Analysis
The pot soil from each treatment was analyzed to check its nutrient level. Soil sampling was done after about 60 days of applying different organic treatments in order to give enough time for proper decomposition and release of nutrients in to the pot soil before seed sowing. The soil samples were left for 3 days to dry properly. The soil pH, Electrical conductivity, Total soluble salts (TSS), Nitrogen, Phosphorus, Potassium, Calcium, Magnesium, Carbonate, Bicarbonate was analyzed according to the analytical methods as described by [21].

Number of days to germination
No significant difference in number of days to germination for both potato and pea was recorded in all the treatments including control. However, the treatment T3 (Banana peel) showed minimum average number of days to germination i.e. 7.75 for potato and 4.00 days for pea. The seedlings in case of treatment T6 (control) took maximum mean number of days for emergence, followed by treatment T2 (Table 1).

Plant height
The treatment T1 showed significantly highest mean plant height (14.75 cm) in potato plant (  Figure 3).

Number of Leaves per plant
The data pertaining to numbers of leaves per plant for the treatments differed significantly in potato (  (Table 3).

Average number of leaves per branch
The data regarding the number of leaves per branch in potato (     Table 3).

Number of nodes
The data regarding the number of nodes in potato after 90 days of seedling emergence revealed that there is significant difference found among treatments ( Table 2). The highest mean numbers of nodes were recorded in the treatment T1 which was 11.50 nodes per plant followed by treatment T3 in which 9.50 nodes were observed (Table 2), whereas the treatment T2 and T6 showed lowest number of nodes (6.5). While no significant difference found among treatments regarding average number of nodes in Pea. The treatment T4 has more nodes per plant (17.50) whereas treatment T6 showed less number of nodes per plant (13.00) ( Table 3).   T1  T2  T3  T4  T5  T6   T6  T5  T4  T3  T2

Tuber weight (grams)
Regarding tubers weight for large, medium and small tubers categories, there is significant difference among treatments in case of weight of large tubers ( Table 4). The treatment T1 had greatest mean weight of large tubers (75.22 g), followed by treatment T3 (61.00 g), however, the weight of medium and small tubers followed comparable trends with non-significant differences among treatments (Table 4, Figure 4).

Average number of Eyes per tuber
In case of average number of eyes per tuber, all the treatments showed no significant effect (P ≥ 0.05) ( Table 4). The data showed that the tubers in treatment T1, T3 and T4 showed comparatively more eyes in case of all the three tubers categories i.e. Large, Medium and Small (Table 4).

Total tubers yield (grams)
A significant difference (P < 0.05) is noted on the average tuber yield obtained per plant among different treatments. The treatment T1 showed significantly higher yield (113.78 g) ( Table 4) followed by T3 in which the mean total yield is 102.34 g. The lowest yield was recorded in treatment T2 and in control treatment T6 (45.97 g; 51.82 g) respectively (Table 4).

Pod Length
The treatment T4 showed largest mean pod length i.e. 7.90 cm (Table 5).

Number of grains per pod
The data regarding the number of grains per pod (   (Table 5).

Single pod weight (g)
The data on the single pod weight (Table 5) showed that the greatest single pod weight observed in treatment T4 (5.10 g), whereas the treatment T2 and T6 showed lowest single pod weight (3.42 g; 3.11 g) ( Table 5).

Total pod yield per plant
No significant difference (P ≥ 0.05) has been noted in terms of total yield obtained per plant among different treatments. However, the treatment T4 showed higher yield (114.3 g) ( Table 5) followed by T3 in which the mean total yield is 66.67 g. The lowest yield was recorded in T6 treatment (46.17 g) ( Table 5).

Physico-chemical analysis of soil
The data regarding the soil samples analysis for each treatment is presented in Table 6. Soil pH for the treatments falls in the alkalinity range with the lowest pH value (8.44) was observed in treatment T6 whereas the treatment T2 and T3 showed higher pH value (8.95; 8.98) ( Table 6).
The higher EC value and total soluble salts (T.S.S) was observed in control treatment T6 i.e. 5.36 and 3.43 respectively whereas minimum EC and T.S.S were in treatment T3 (1.14 and 0.72) respectively. The treatment T4 and T3 showed higher organic matter value i.e. 2.05 and 1.79% respectively (

Discussion
Organic fertilizers are used to enhance soil quality and add nutrients essential for plant growth. In present research work soil is supplemented with different household organic waste as fertilizers for Potato (Solanum tuberosum L.) and Pea (Pisum sativum L.  resulted in minimum average number of days to germination after seed sowing for both vegetables (Table 1). This is because Bananas peel is rich in minerals including potassium, phosphorus and calcium. Our results are in consistent with Patrick, (2017) [22]. Ascher et al. (1994) [23] reported that phosphorus plays a significant role in seed germination and viability. Soils having phosphorus deficiency oppressed the initial plant growth. Root growth has not only been increased by phosphorus but it also enhances plant's early maturity [24].
Regarding average plant height after 30, 60 and 90 days it was observed that plants of treatment T1 (egg shell powder) has shown greater plant height in potato crop ( Table 2). This may be due to the fact that eggshell is source of calcium and in the present research the treatment T1 (eggshell powder) increased the soil calcium level (Table 6). Kris, (2010) [25] reported that the water used to cook hard boiled eggs is a valuable source of calcium for growing vegetables. Our results are compatible with the findings of Nikose (2015) [26]  In our study, the use of used tea waste also had positive effect on the overall growth of pea plant (Table 3). Tea leaves contain potassium (K), phosphorous (P), Nitrogen (N) and Tannic acid, which are important nutrients for plant growth. The tea grounds when decompose increase soil nutrients which in turn promotes the activity of the beneficial microorganisms thus improve soil oxygenation, which strengthen the root system of plants. Used tea waste is a source of nitrogen [33] which plays a most important role in various physiological processes and our treatment T4 (used tea waste) also increased the soil nitrogen level (Table 6). Bloom, (2015) [34] reported that nitrogen encourages the uptake and utilization of other nutrients including potassium, phosphorous and controls overall growth of plant.
The average leaf area of the pea plant has also been higher in treatment T4 (used tea waste). The possible reason for this is reported by Ahmad et al. (2009) [35] that optimum rate of N increases photosynthetic processes and leaf area production and the maximum leaf area and total leaf biomass are a determinant of higher crop yield [36].
In the present study, the organic fertilizers effect on potato and pea yield presented in (Table 4 and Table 5) revealed that the treatments T1 (eggshell powder), T3 (banana peel), T4 (used tea waste) as compared to other treatments showed positive effect on yield. According to [37], the potassium increases crop yield and improves tuber quality. Cao and Tibbitts (1991) [38] indicated that low K not only decrease potato growth, but also disturb nutrient balance among major cations. The effect of organic fertilizers on potato tuber size presented in (Table 4) revealed that the treatment T1 (eggshell powder) showed larger tubers as compared to other treatments. It may be due to the fact that the eggshells add calcium to the soil (Table 6). Our results are in agreement with [39] who reported that calcium had a role at the time of tuber formation and its deficiency causes many plant abnormalities especially fruit and storage organs. Walker, and Csinos (1980) [40] reported that both potatoes and peanuts have underground storage organs and [41] found that calcium fertilization in peanuts can enhance peanut grade and yield. Our results for greater pea yield in treatment T4 (used tea waste) ( Table 5) is may be due to increased soil N level (Table 6) and is also DOI: 10.4236/as.2018.96049 713 Agricultural Sciences supported by the findings of [42] and [43] who were of the opinion that increased nitrogen fertilization had significant effect on yield and yield related characteristics in peas. In the present study the total yield as number of pods per plant, and number of grains per pod, pod size has also been found higher in treatment T4. Woyke, and Rzymowska (1986) [44] reported that pea yield is positively affected by increasing dose of nitrogen which facilitates vegetative growth and nodulation and increases green pod yield [45] and [46] [47].

Conclusions and Recommendations
The present study showed that different household organic fertilizers gave better growth and yield response in case of both potato and pea crops. The treatments T1 (Eggshell), T3 (Banana peel) and T4 (Used tea waste) not only increased plants growth but also had positive impact on yield in terms of number of tubers and pods per plant. It is recommended that the use of these organic fertilizers in kitchen gardens is economically important where it not only replenishes soil organic matter but also gives the sustainable production. However, further research is needed under field conditions to collect waste materials like eggshells, fruit peels, tea waste from the industries and homes to know the effect of various organic household waste used as fertilizer on other plants especially vegetables and to evaluate their effects on plants when applied in larger quantities. There were certain limitations in the present research work regarding accurate measurement of quantities of various treatments, because the amount of every treatment in terms of volume can be different if added on equal weight basis, and some treatments are less in weight than others, thereby gaining more volume in bulk which results in a variety of different quantities for different treatments, so it is also recommended to standardize their quantities in terms of weight units for future studies and field applications.